Many dental and orthodontic procedures can benefit from accurate three-dimensional (3D) descriptions of a patient's dentation and intraoral cavity. In particular, it would be helpful to provide a three-dimensional description of both the surface, and internal structures of the teeth, including the enamel and dentin, as well as caries and the general internal composition of the tooth volume. Although purely surface representations of the 3D surfaces of teeth have proven extremely useful in the design and fabrication of dental prostheses (e.g., crowns or bridges), and treatment plans, the ability to image internal structures including the development of caries and cracks in the enamel and underlying dentin, would be tremendously useful, particularly in conjunction with a surface topographical mapping.
Historically, ionizing radiation (e.g., X-rays) have been used to image into the teeth. For example, X-Ray bitewing radiograms are often used to provide non-quantitative images into the teeth. However, in addition to the risk of ionizing radiation, such images are typically limited in their ability to show features and may involve a lengthy and expensive procedure to take. Some intraoral features such as soft tissues, plaque and soft calculus may not be easily visualized via x-ray because of their low density. Other techniques, such as cone beam computed tomography (CBCT) may provide tomographic images, but still require ionizing radiation.
Thus, it would be beneficial to provide methods and apparatuses, including devices and systems, such as intraoral scanning systems, that may be used to model a subject's tooth or teeth and include both external (surface) and internal (within the enamel and dentin) structures and composition using non-ionizing radiation. The model of the subject's teeth may be a 3D volumetric model or a panoramic image. In particular, it would be helpful to provide methods and apparatuses that may use a single apparatus to provide this capability. There is a need for improved methods and systems for scanning an intraoral cavity of a patient, and/or for automating the identification and analysis of dental caries.